* 


CONVERSION  OF  TURPENTINE  INTO  TERPINEOL 

BY 

ISAAC  C.  SAWYER 


THESIS 

For  the  Degree  of 
BACHELOR  OF  SCIENCE 
IN  CHEMICAL  ENGINEERING 

IN 

COLLEGE  OF  LIBERAL  ARTS  AND  SCIENCES 
OF  THE 

UNIVERSITY  OF  ILLINOIS 


1921 


UNIVERSITY  OF  ILLINOIS 


1.U 19&L. 


THIS  IS  TO  CERTIFY  THAT  THE  THESIS  PREPARED  UNDER  MY  SUPERVISION  BY 


ENTITLED .TIC CMYSIiSIQlL  .QE...TUEP.KimH.I r. 3 ?.l 


IS  APPROVED  BY  ME  AS  FULFILLING  THIS  PART  OF  THE  REQUIREMENTS  FOR  THE 
DEGREE  OF [ AA > — t - — ^.0. i... . L. ..  1 


HEAD  OF  DEPARTMENT  OF 


Digitized  by  the  Internet  Archive 
in  2015 


https://archive.org/details/conversionofturpOOsawy 


THE  SOLUTION  OB  THE  PROBLEM  PRESIN T HD  IH  THIS  THESIS 
WAS  LADE  POSSIBLE  THROUGH  THE  VALUABLE  ASSISTANCE 
GIVEN  AS  BY  PROFESSOR  ROlGEE  AD  AGS.. 

I WISH  TO  EXPRESS’  NY  SINCERE  APPRECIATION  POR  TH 
WHOLEHEARTED  INTEREST  WHICH.  OR.  aDaUS’  HAS  CONSTANTLY 


SHOWN  IN  ...Y  WORK. 


■ 


contents. 


PAGES 


1..  INTRODUCTION  - --  --  --  --  --  --  --  --  -1-3. 

11..  HISTORICAL  - --  --  --  --  --  --  --  --  - 4-0 

(A)  TURPENTINE  - --  --  --  --  -- 

(B ) TERPIN  HYDRATE  - --------  6 

(C)  TERPIN SOL  ------------  7 

111..  THE  PROBLEM  - --  - - --  --  --  --  --  --  9 

IV. .  THE  .METHOD  OF  ATTACK  - --  --  --  --  --  --  10-12 

V. .  DISCUSSION  - --  --  --  --  --  --  --  --  - 13-15 


VI..  experimental 

(A)  EXPERIMENTS  WITH  ALCOHOL, 


ACIDS  AND  SAWDUST  - - - - - - -16-17 
(3)  HZCHaKICaL  STIRRER,  ACID 
CONCENTRATIONS  AND 

TEMPERATURE  ----------  18 

(C)  ISOLATION  OF  TERPIN  HYDRATE  - -'19-20 

(D)  RECRY  STALL  1 Z AT  I ON  OF  TH  PIN 
HYDRATE  IN  ALCOHOL  ------21-22 

(E)  TREATMENT  OF  TERPIN  HYDRATE 

TO  FORM  TERPINEOL  -------  23 

VII..  CONCLUSION  - --  --  --  ----------  - -24-25 


VIII..  3 13L  IQGRaPKY 


X.  INTRODUCTION. 

Terpineol  is  ari  un saturated  alcohol  with  on»-  double  bond. 
It  is  a tertiary  alcohol  and  exists  in  four  isotropic  forms 
n Ly  alpha,  beta,  gamma,  and  delta.  Each  form  has  different 


physical  properties;  the  first  form  , alpha  terpineol,  has 


the  empirical  formula  CwHvO  . Its  structure  is  C1^CX 


- 

✓ * >* 


X 


H- 


Alpha  terpineol  has  the  molecular  weight  of  154.19,  a specific 
gravity  of  0.92b,  a melting  point  of  35  degrees,  a boiling  point 
of  218  degrees,  and  is  a white  transparent  crystal  which  is 
insoluble  in  water. 

■ — p ] n h 

Beta  terpineol  has  the  smructux ; 01%-CDH  ^ . It  h 

a m 3 

> cific  gravity  of  0.923  a melting  point  of  32  to  33  degrees, 
a boiling  point  of  210  degrees,  and  is  very  slightly  soluble 
in  water  and  very  soluble  in  ether  and  alcohol. 

In  gamma  terpineol  the  double  bond  is  between  the  side  chain 

^ r ^ ✓«£ 

an o t h e r i n g . It  has  t n ©structure  - ^C=.c  . T h e 

w a.  w m.  •'  3 

melting  point  is  60  to  70  degrees. 

Delta  terpineol  is  not  known  to  exist  in  the  free  state.  If  it 
did,  it  would  have  the  foi  C|„Hw0  and  the  structure 

_ r>  u 

/J  * >3  ^ 3 

ClfO  >CK-CQR 

* ^V-i  i _ o -i  n ; : 

- £ ^ 1 H J J 

The  different  forms  of  terpineol  are  isolated  by  freezing. 
Terpineol  is  made  in  the  liquid  form.  The  fact  that  it  exists 
in  this  state  is  probably  due  to  small  quantities  of  a struct- 
urally isomeric  impurity.  ( 1 ) . Terpineol  has  a high  specific 
refraction  of  ( 1.46  to  1.47  ),  The  fact  that  it  unites  with 
nyl-carbiraide  forming  phenyl-urethane,  CjH^O  jfj. 


that  terpineol  is  a tertiary  alcohol.  Terpineol  also  unite 
with  one  molecule  of  nitrosyl  chloride  forming 


\ - 


3 


C J 


■ ST  a 


These  last  two  reactions  prove  that  terpineol  has  one  double 

bond.  When  terpineol  is  oxidized  with  chromic  acid, . it  forms 

^-00  - 


y,  -■ 


trioxy  t r )i  ..  - -CO  w.  The  structure  of  ter- 

c a wwj 

pineol  was  proven  by  W.H.  Perkin  Jr.,  who  synthesised  terpineol 
by  starting  with  ethyl  cyanoacetate  and  ethyl -B-iodopropionat e. 


p pv  1 _ — n l \ 

c:  — , — :oochv  2 C]n-CE-Cd0-Qr  - =c-c<~ 

a k>  a ' x sr 

hydrolysis  with  dilute  HC1 

-C  -COOK 

CO  - boil  with  ( q ' ) ) - istill 

' ^Ob-O  -COOL  5 * 


/CH  CH„  : ^ 

_ , * >>•  TRSAT  with  Mg 


. _ 4 
a a 


X 


. 


n - 

t COCI-CH  >0  -C  3 


. '•!  M ' 

* * 


il  HBr  ’ Q^jpocR  ^>Ci3r— CHg  # KaQH  rhve 

C]  f - ~dz 


:ooi 


/ w x 

7 ^ p - 

^ _ if 

w a /J 


pii  . nyj 

- « ^ n 

' ^ , --r-i  _ rr  1.7 

^ X J.  O j.  ^ vu  i 

\ ^ \ ^ 

1 w * 3 

T erpin eol 


con 


’ 


Per. Lein  oxidized  terpineol  and  obtained  dicarboxylic  acid  and 


■ c lie  acid  c 0 ^C:  - 

■ 3 -,n  * 3 — o - 

.-i;  ^ n ' u 

L/  J -i-41  . w i 


vJ  / p 

j:COH-CH  -olus  CH— coon. 


I _ 

/ z 

']  ' — Q p 


£ i"i:"  ^ 


an 


‘ -r  - 

x 


Terpineol  occurs  in  active  and  inactive  forms  in  lovage 
oil,  cardemom  and  morjorara  oil.  The  levo  form  occurs  in  niaouli 
oil  and  the  inactive  form  in  cajeput  oil.  Isomeric  oodif ications 
of  terpineol  r,r«  present  in  lilac,  tuberose,  mimosa,  plan,-,  and 


. 


. 


' 


3. 


lily  of  the  valley  flower  oils.  Terpineol  is  a volatile  oil 
and  contains  oxygen  accompanied  by  oxygen-free  terpenes  and 
some  resinous  or  waxy  materials. 


' 


Pfc.fi 


II.  HISTORICAL. 

Nearly  all  plants  contain  volatile,  odoriferous  liquids 
called  essential  oils  many  of  which  possess  a pleasant  odor  or 
taste,  and  are  used  in  the  manufacture  of  essences  and  perfumes, 
many  of  them  are  also  used  in  medicine,  host  essential  oils 
are  complex  mixtures,  and  although  the  characteristics  of  any 
one  such  oil  are  usually  due  to  the  presence  of  some  particular 
compound,  this  compound  may  be  accompanied  by  many  others.  It 
often  happens  that  two  or  more  essential  oils  have  two  or  more 
components  in  common,  and  yet  differ  entirely  in  smell,  because 
each  contains  in  addition  some  highly  odoriferous  compound 
which  does  not  occur  in  the  others.  The  terpene  can  not  be 
accurately  defined,  it  is  more  particularly  employed  to  denote 
certain  unsaturated  hydrocarbons  of  the  molecular  for. ml  ',//<• 
Turpentine,  terpin  hydrate,  and  terpineol  are  in  the  terpene 
groups 

(A)  TURPENTINE. 

The  most  abundant  and  the  most  generally  known  of  all 
the  essential  oils  is  turpentine,  which  is  obtained  by  making 
shallow  cuts  in  the  stems  of  pine  trees  or  coniferae,  and  coll- 
ecting the  sap  or  juice  which  flows  out.  When  this  sap  or  juice 
is  distilled  it  yields  ordinary  or  oil  of  turpentine  and  spirits 
of  turpentine.  Turpentine  is  a widely  used  solvent  and  becomes 
scarcer  each  year,  so  that  lately,  even  the  old  stumps  have 
been  utilized  to  produce  a cheap  grad'*.  Oil  of  turpentine  is 
a colorless,  mobile  liquid  of  specific  gravity  of  0.86,  boiling 
t 5.  It  considerable  variations  in  prop- 

erties according  to  the  species  of  pine  from  which  it  has  been 


obtained..  The  oil  has  a well  known  odor  which  is  probably  due 
to  small  quantities  of  substances  formed  it  by  oxidation.  On 
exposure  to  moist  air  it  is  converted  into  resin  and  a variety 
of  oxidation  products.  Th^  oil  is  practically  insoluble  in 
r.  . t r but  is  miscible  in  most  organic  liquids.  TIUrpentin  Li 
a mixture  the  principal  component  of  which  is  a hydrocarbon 
known  as  pinene.  Pinene  is  a colorless  mobile  liquid,  specific 
gravity  of  0.858  at  20  dogr» i s,  having  a odor  of  turpentine. 

It  boils  at  155  degrees  and  is  readily  volatile  in  steam.  Pinene 
combines  directly  with  two  atoms  of  bromine,  yielding  a crystal 
of  dibromide  and  with  one  molecule  of  hydrogen  chlorj 

giving  pinenehydrochloride  which  has  the  app  arance  and  odor 


The  other  constituents  of  turpentine  are  sylvestrene  and  dipen- 


Dipentine  has  a specific  gravity  of  0.85,  and  a boiling  point 
of  181  degrees.  It  is  insoluble  in  water  and  very  soluble  in 
alcohol  and  ether.  The  structure  of  sylvestrene  has  not  been 
determined  but  it  is  very  probable  that  it  is  similar  to  that 
of  dipentene. 


of  camphor.  The  structure  of  pinene  is  C 


term,  The  structure  of  dipentene  is 


. 


. 


. 


. • 


. 


- 


. 


. 


3ag< 


(B)  TERPIN  HYDRATE. 

Terpin  hydrate  is  a white  crystalline  substance  that  has 
a melting  point  of  117  degrees  and  a boiling  point  of  the  same 
as  that  of  terpin.  This  because  terpin  hydrate  decomposes  into 
terpin.  Terpin  has  a boiling  point  of  258  degrees.  The  struct- 

0 3 

u re  of  terpin  hydrate  is  ^ COH-CH  OH— CH_  . It  can  be 

CH3 

HOH 

mad  ? by  hydrating  terpineol  in  the  presence  of  60  to  65  percent 

sulphuric  or  phosphoric  acid  at  a temperature  of  BO  degrees. 

Terpin  hydrate  will  not  steam  distill.  Its  chief  use  is  for  the 

manufacture  of  terpineol  and  it  is  also  used  to  a considerable 

extent  in  medicine.  In  the  National  Formulary,  fourth  edition, 

there  are  two  prescriptions  given  in  terpin  hydrate  is  used. 

Elixir  Terpini  Hydratis  et  Codeinae. 

Codeine,  two  grammes  -----------  2gm. 

Elixir  of  Terpin  Hydrate,  a sufficient 

quantity  to  make  one 
thousand  milliliters  - - - 


1000  mils. 

Elixir  Terpini  Hydratis  et  Diacetylmorphinae. 

D i ac  e ty lino rphin e Hy d ro chi o r i d e , 

Twenty s even  hundredths  of 
a gramme  --------  -0.  27  gm. 

Elixir  of  Terpin  Hydrate, 

A sufficient  quantity,  to 
make  one  thousand  millili- 
ters ------------ 


1000  mils. 

Dissolve  the  diacetylmorphine  hydrochloride  in  sufficient 
of  the  elixir  to  measure  one  thousand  milliliters  and  filter. 


* 


\ 


. 

■ 


. 

- 

Page  7. 


(C)  TERPXl'iSOL,  . 

In  all  probability  the  knowledge  of  terpineol  dates  back 
to  the  days  of  tne  Chaldeans.  These  people  were  well  learned 
in  tne  making  of  perfumes  and  therapeutics,  because  of  .its 
therapeutic  property,  it  was  used  by  these  people  in  there  embalm- 
ing fluids.  Probably  the  plant  from  which  they  obtained  terpin- 
eol was  the  Syringa  Vulgaris.  This  plant  is  a native  of  Persia 
but  fully  acclimated  in  Europe  and  America.  It  is  known  in  this 
country  as  lilac  and  the  oil  from  its  flowers  contain  a fraction 
between  210  and  220  degrees  which  possesses  a lilac  odor  of  a 
very  pronounced  degree.  This  fraction  is  terpineol.  To  get  the 
sweet  and  flowery  odor  from  terpineol  it  should  be  diluted  with 
very  pure  alcohol.  This  dilution  is  eight  ounces  of  terpineol 
to  one  gallon  of  alcohol.  Concentrated  terpineol  will  not  give 
a sweet  odor,  because  the  odor  given  off  is  to  intense.  Flowers 
only  give  off  small  quantities  of  perfume  at  a time  so  the  dil- 
uting of  this  concentrated  terpineol  is  merely  duplicating  con- 
ditions existing  in  nature.  All  lilac  flower  oils  contain  a 
large  percentage  of  terpineol.  Many  shadings  of  this  lilac  -odor 
are  obtained  by  varying  the  percentage  of  this  ingredient.  The 
odor  groups  of  terpineol  are  probably  the  OH  and  the  CH3 groups-.. 

Traces  of  by-products  sometimes  present  in  terpineol 
not  large  enough  to  be  found  by  chemical  tests  will  often  ser- 
iously interfere  with  the  odor.  To  eliminate  impurities  the  oil 
should  be  vacuum  distilled  three  or  four  times.  The  by-product 
most  likely  to  be  present  in  terpineol  is  turpentine  and  it 
can  be  determined  by  fractionating  a small  sample  of  the  oil: 
if  ten  percent  of  the  first  run  of  the  distillate  shows  a decided 


- 


• 

, 

. 

• 

. 


Pare  8 


change  in  the  angle  of  rotation  towards  the  left,  the  possibil 
ity  of  its  presence  is  excluded.  The  common  terpineol  , much 
used  as  a soap  scent,  is  a syrupy  oil  looking  like  glycerine.. 
During  the  last  century  it  has  been  manufactured  by  the  very 
expensive  method  of  allowing  the  mixture  of  turpentine,  ethyl 
alconol  and  nitric  acid  to  stand  for  seven  days. 


■s 


- ' 


Page  V. 


III.  THU  PKOBLEk. 

The  problem  was  to  work  out  a process  which  could  be 
used  on  a commercial  scale  for  the  conversion  of  turpentine 
into  terpineol.  Tin.  > 1 ct  , rora  th<  _ • ter- 

pene  oils,  because  of  its  low  cost  and  plentiful  and  readily 
accessible  supply.  The  ideal  striven  for  w as  to  obtain  the 
maximum  yield  at  the  minimum  cost  in  the  shortest  time  possible. 


. 


. 


Page  10. 


IV.  CJiB  METHOD  OP  ATTACH. 

The  first  in  the  solution  of  this  problem  was  to  obtain 
all  the  information  ppssible  about  the  different  substances 
which  were  to  be  experiment  with.  Some  of  this  information  was 
found  in  organic  text  books  and  the  rest  of  the  information  was 
obtained  from  Richter,  Beilstein  and  various  serials.  All  the 
references  that  had  direct  bearing  on  the  problem  were  abstract- 
ed, The  serials  which  were  referred  to  were  The  Jour.  Chem.  ’oc.  , 
Jour.  Am.  Chem.  Soc. , Bull.  soc.  chim. , Patent  Anmeldung,  Fried - 
1 a end  or,  Berichte,  Jahresbericht e,  Monatsch,  Z.Phys.  Chem.,  Arch. 
Pharm. , J.  prakt.  Chem.  , J.  RUSS.  Phys.  Chem.  Soc. , Comptes 
rendus,  Chem.  Z'entr.  , J.  Biol.  Chem.,  then  some  information  v:as 
obtained  from  Vanino,  and  the  U..S.  Patents.  The  following  pro- 
cesses are  abstracts. 

TERPIU  HYDRATE.  (1). 

Take  400  grams  of  refined  American  or  French  oil  of 
turpentine,  350  c.c.  of  alcohol  specific  gravity  0.831,  (80  vol. 

of  alcohol  20  vol.  of  water)  and  80  c.c..  of  nitric  acid  specific 
gravity  1.3,  and  let  this  mixture  remain  in  a wide  shallow 
porcelain  dish  at  normal  temperature  for  one  day.  Then  neutral- 
ize it  with  alkali,  filter  dry  and  recrystallize  in  96  percent 
alcohol. 

Terpin  hydrate  is  soluble  in  32  parts  of  boiling  water, 

250  parts  of  water  at  15  degrees,  10  parts  in  alcohol,  100  parts 
in  ether,  200  parts  in  chloroform,  slightly  soluable  in  turpentin  . 


1.  J.,Chem.  Soc.  (1899) 


. 


1 

Page  11. 


TERPIN  HYDRaTL  (2). 


Agitate  terpineol  with  80  percent  phosphoric  acid  at 
30  degrees, it  becomes  a homogenous  solution  and  crystals  of 
terpin  hydrate  separate.  Less  complete  action  is  formed  by  60 
percent  sulphuric  acid. 


Treat  terpinene  dihydrobromide  at  zero  degrees  with 
silver  acetate  in  glacial  acetic  acid.  Treat  limonene  hydro- 
chloride with  an  excess  of  two  percent  aqueous  potash  at  50  to 
60  degrees. 


Treat  linalool  in  three  times  its  weight  of  acetic  acid 
and  one  half  percent  sulphuric  at  a temperature  below  20  degrees 
to  obtain  parts  of  d -terpineol  and  10  parts  geraniol. 

d-Linalool  is  converted  in  a similar  manner  to  1-terpineol 
by  using  formic  acid. 


Terpineol  is  obtained  by  mixing  pinene,  alcohol  and 
nitrous  acid  purified  from  nitric  acid  and  leaving  the  mixture 
at  ordinary  temperature  for  about  two  months.  Neutralize  and 
steam  distill  at  reduced  pressure. 


To  a 100  parts  of  linalool,  geraniol  and  citron  el  mixed, 
at  ten  to  fifteen  degrees  with  a 100  parts  of  acetic  acid  and 
three  to  ten  parts  of  sulphuric  acid.  Agitate  the  mixture  and 
keep  the  temperature  below  30  degrees.  After  the  mixture  becomes 
homogenous  mix  it  with  water  so  that  the  oil  is  separated. _ 


Alpha  Terpineol  (3) 


TERPINEOL  (4). 


TEBPIN250L  (5). 


TELPILEOL  (6). 


Chem.  Soc. 


ii 


ti  ti 


ii 


(1917). 

(1907). 

(1899). 


5.  Comptes  rendes  (1901). 

6.  Friedlaender  (1394-1897) 


* 


fr  r 

. 

. 

* 


. 


Page  12. 


TERPIN  HYDRATE  (7). 

Saturate  saw  dust  with  turpentine  and  treat  the  mixture 
with  a dilute  solution  of  sulphuric  acid,  ilacerate  the  solution 
and  remove  the  acid  and  non-converted  oil.  Wash  trie  substance 
with  a solution  of  sodium  carbonate.  Extract  the  terpin  hydrate 
from  the  saw  dust  with  a solvent. 

TEKPINEOL  (3). 

Take  three  of  greek  oil  of  turpentine  43  degrees  dextra- 

rotary  and  add  with  constant  stirring  two  parts  toluic  sulphonic 

% 

62  percent.  The  temperature  is  kept  at  19  degrees.  Continue 
stirring  until  a homogenous  solution  is  formed..  This  takes  from 
five  to  seven  hours.  Then  add  four  to  five  parts  of  water, 
neutralize  and  steam  distill  the  separated  oil. 

TERPJNEOL  ( 9 ) . 

Treat  25  grams  of  terpin  hydrate  with  a 100  c.c.  of 
sulphuric  acid,  33  percent.  Reflux  mixture  for  one  hour.  Separate 
the  oil,,  neutralize  and  steam  distill. 


7..  (J.  S.  Patents.  Vol.  126.. 

3,  Friedlaender  (1907,-1910). 
9.  Annul en  der  Chemie  (230). 


' 


. . 


. 


Page  13. 


V.  DISCUSSION. 

It  is  obvious  from  the  processes  which  are  given  on  the 
preceding  p ;;es  that  they  are  acid  concentration  and  temperature 
reactions.  Then  if  the  proper  concentration  is  kept  and  the 
temperature  allowed  to  vary,  the  exact  temperature  can  be  de- 
ter airied  at  which  the  .maximum  yield  is  obtained  with  that  con- 
centration.After  this  temperature  is  determined,  it  should  be 
kept  constant  and  the  cone entrat ions  varied  until  a maximum 
yield  is  obtained.. 

IN  these  processes  there  is  not  one  in  which  terpineol 
is  made  directly  from  turpentine..  This  would  lead  one  to  be- 
lieve that  if  it  were  possible  to  make  terpineol  from  turpentine 
directly  that  some  one  would  have  done  it..  It  is  also  obvious 
from  these  processes  that  turpentine  can  only  be  converted  into 
another  substance  by  treating  it  with  a strong  acid  at  a low 
temperature  and  that  terpineol  is  made  by  the  treatment  of  ter- 
pene  oils  v/ith  a dilute  acid.  Then  if  turpentine  will  only 
change  its  form  when  treated,  with  an  acid  of  high  concentration, 
it  would  be  impossible  to  make  terpineol  direct  from  turpentine, 
because  terpineol  is  made  by  an  acid  of  low  cone entrat ion  react- 
ing ith  a terpine  compound.  Van in o ’ s method  for  the  preparation 
of  terpin  hydrate  could  not  be  used  on  a commercial  basis,  be- 
cause of  the  expense.  In  this  process  alcohol  is  probably  used, 
because  it  can  be  diluted  so  that  it  will  have  the  same  specific 
gravity  as  turpentine..  This  alcohol  would  have  a stronger  ten- 
dency to  bring  the  acid  into  contact  with  the  turpentine  than 
a liquid  of  a higher  specific  gravity.  The  trouble  with  most 
of  the  processes  in  the  literature  is  that  the  acid  is  in  one 


. 


, 


. 

. 


. 


. 


Page  14. 


layer  and  the  turpentine  is  in  the  other.  For  this  reason 
it  takes  several  days  for  the  reaction  to  taxe  place.  If  the 
concentrated  acid  is  added  directly  to  the  turpentine  at  ordin- 
ary temperatures  , it  would  decompose  the  turpentine.  One  way 
to  "bring  the  acid  into  contact  with  the  turpentine  is  to  sat- 
urate the  saw  dust  with  turpentine  and  treat  this  mixture  with 
acid.  If  it  were  possible  to  treat  the  turpentine  with  an  acid 
solution  that  would  diffuse  into  the  turpentine  then  the  reaction 
would  take  place  in  a few  minutes  but  the  turpentine  has  a strong 
tendency  to  exclude  any  acid  solutions.  In  the  process  in  which 
terpin  hydrate  is  made  from  terpineol  by  the  agitation  of  a 
solution  of  terpineol  and  a strong  acid  , one  might  be  lead  to 
believe  that  it  would  be  possible  to  make  terpin  hydrate  by  a 
similar  reaction  from  turpentine.  In  the  experimenting  one 
should  attempt  to  find  the  cheapest  acid  that  will  ;ive  'ood 
results.  If  a process  is  worked  out  for.  the  conversion  of  tur- 
pentine into  terpin  hydrate,  the  next  step  is  to  work  out  a 
process  for  the  conversion  of  terpin  hydrate  into  terpineol.. 
in  this  process  the  difficulty  will  arise  as  to  how  to  isolate 
the  terpin  hydrate  from  the  mixture.  Terpin  hydrate  will  de- 
compose in  € strong  acid  solution  if  the  temperature  is  not 
kept  ciose  to  zero  degrees.  Brobably  the  best  way  to  treat  this 
difficulty  is  to  dilute  the  mixture  with  ice  and  suck  the  ter- 
pin hydrate  as  dry  as  possible  and  then  neutralize  the  mixture 
with  a dilute  alkali.  The  remaining  turpentine  can  be  separated 
from  the  terpin  hysrate  by  steam  distillation.  Terpin  hydrate 
can  be  recrystallized  in  9 G percent  alcohol. 

In  experimenting  with  terpineol  it  is  best  to  try  acids 


. 


. 

. 

i 


Page  15. 

of  weak  cone entrat ions,  because  acids  of  strong  concent  rat  ions 
will  convert  terpin  hydrate  or  oils  of  the  terpene  group  into 
oils  of  lower  boiling  points  than  that  of  terpineol  or  the  strong 
acid  will  decompose  the  substance  into  resinous  matter..  In  the 
process  where  terpineol  is  made  from  linalool,  geraniol  and 
citronel  only  one  percent  of  sulphuric  acid  is  used,  how,  if 
terpin  hydrate  is  treated  with  one  percent  of  sulphuric  acid 
at  ordinary  temperatures  there  is  no  reaction  and  if  terpin 
hydrate  is  refluxed  with  33  percent  of  sulphuric  , it  is  con- 
verted into  oils  of  lower  boiling  points  than  that  of  terpineol.. 
Since  terpin  hydrate  will  react  with  acids  of  low  concentrations 
at  high  temperatures,  then  tests  should  be  made  along  these 
lines.  A certain  amount  of  terpin  hydrate  should  be  refluxed 
with  dilute  sulphuric  which  in  each  test  has  a different  con- 
centration. A series  of  these  tests  should  be  run  until  that 
concentration  is  found  which  gives  the  maximum  yield  from  terpin  • 
hydrate.  Enough  solution  should  be  used  in  each  test  so  as  to 
completely  cover  the  terpin  hydrate.  Then  the  oil  which  sep- 
arates should  be  neutralized  and  fractionated  to  determine  the 
amount  of  terpineol.  The  time  should  be  varied  so  as  to  deter- 
mine the  shortest  time  necessary  to  complete  the  reaction. 

The  data  obtained  from  the  experiments  will  show  how  to  get 
the  maximum  yield  of  terpineol  from  turpentine  at  the  minimum 
cost  in  the  shortest  time  for  the  most  convenient  process. 


, 


. 


. 


. 


Page  16. 


VI.  EXP31U  I iiEK  T aL  . 

(a)  The  first  in  the  experimenting  was  to  find  which 
acid  gave  the  best  results.  The  same  amount  of  turpentine  and 
the  sa ue  amount  of  alcohol  or  acetic  acid  was  used  in  each  one 
of  these  tests..  In  some  of  the  processes  found  in  the  literature 
terpin  hydrate  was  made  from  turpentine  by  treating  a certain 
amount  of  the  turpentine  with  an  equal  amount  of  the  acetic 
acid  or  the  alcohol.  The  acids  which,  might  be  used  in  this  pro- 
cess are  sulphuric,  nitric,  hydrochloric  and  formic.  The  react- 
ions were  carried  out  in  wide  porcelain  dishes.  The  data  obtained 
from  these  tests  is  in  the  following  table. 

Turpentine  Alcohol  Acetic  Acid  20gr. Acid  Temp.  Time  Yield 
sp.gr.  0.  875.  95;£ 


lOOgr.  lOOgr. 

II  

" 100 

II 

" 100 

ff 

" 100 

II 

it  100 

II  

Prom  the  result 
sulphuric  acid  gives 
a greater  tendency  to 


100 


100 


100 


100 


sulphuric  25-30  7 days  13gr 

Q 


n i t r i c 


hydrochloric  11 


phosphoric 


f o rm i c 


1 00 


10 


s in  the  above  table  it  is  obvious  that 
the  largest  yield  or  that  turpentine  has 
react  with  sulphuric  than  with  any  of  the 


. 

. 


. 


. 


. . 


Page  17 


other  ac ids  that  were  used.  .T ust  what  et  1 ec t the  acetic  c i<j 
lc ) ^ /'vn.  It  is  probable  th 

has  a greater  tendency  than  trie  acetic  acid  to  bring  the  sulphuric 
into  contact  with  the  turpentine.  If  this  is  the  case,  it  is 
very  1 _L  rC  ely  water  will  give  the  same  results  when  substituted 
for  tne  alcohol,  if  the  mixture  is  agitated.  In  the  process  in 
which  saw  dust  was  saturated  with  turpentine.  It  was  found  that 
if  the  mixture  had  stood  for  24  hours  the  reaction  was  complete- 
ed.  This  goes  to  show  that  the  time  of  the  reaction  is  directly 
proportional  to  the  amount  of  the  acid  brought  into  contact 
with  the  turpentine.  The  rea.son  why  saw  dust  could  not  be  used 
on  a commercial  scale  is  that  most  of  tne  solvent  required  to 
extract  the  terpin  hydrate  is  absorbed  by  the  saw  dust.  The  best 
way  to  bring  all  of  the  turpentine  into  contact  with  the  acid 
is  to  ,use  a mechanical  stirrer. 


. 


. 


80 


70 


40 


go 


L 0 


20  30  40  50  60 

PEHGELTTjfiGE  OP  SULPHURIC-  ACID  SOLUTION 


i'J 


Page  18. 


{B ) The  following  data,  are  tne  results  of  a series  of  ex- 
periments done  in  a mechanical  stirrer.  The  concentration,,  tem- 
perature and  time  were  varied  until  the  maximum  yield  was  ob- 
tained. 


Turpentine  Water  Sulphuric  Temperature  Hours  Terpin  Hydrate 
sp..gr.  0.  875  sp.  gr.  1.845 


37. 5gr. 

SOgr.  20gr. 

25  de. 

24' 

15gr. 

If 

75 

25 

It 

II 

17 

11 

70 

30 

H 

If 

25 

11 ; 

6b 

35 

0 

H 

37 

55 

48 

n 

15 

48 

If 

50 

60 

it 

tr 

56 

it 

45 

55 

fi 

itT 

65 

i» 

40 

60 

ft 

tr 

71 

tt 

35 

65 

if 

ill! 

no  yield 

H 

30 

70 

it 

in 

ft 

n 

43 

57 

If 

if 

68 

fi 

37 

63 

If  : 

rn 

70 

n 

41 

59 

ft 

if; 

71 

ft 

39 

61 

it 

If 

The  i 

max imum 

yield  of  terpin  hydrate 

was  o*b 

tained  by  using 

60  grams  of 

sulphuric  acid..  This 

con cent rat  ion  is 

about  55  per- 

cent  sulphuric..  The 

yield  is  80 

percent  of 

the  turpentine.  About 

ten  percent 

of  this 

unconverted 

turpentine 

can  be 

recovered. 

' 


. 


DIAGRAM  OF 


THREE  MECHANICAL  STIRRERS  OPERATED  BY  ONE  MOTOR. 


Page  19. 


(C)  The  next  experiments  are  on  the  isolation  of  terpin 
hydrate  from  an  acid  mixture.  If  the  temperature  of  the  red 
colored  homogenous  mixture  obtained  by  the  conversion  of  turpen- 
tine with  sulphuric  acid,  is  allowed  to  rise,  the  mixture  will 
decompose  into  a dark  colored,  resinous  substance.  This  mixture 
is  obtained  in  the  experiment  where  60  grams  of  sulphuric  is 
used.  It  was  found  that  the  best  way  to  convert  this  red  colored 
mixture  into  terpin  hydrate  and  separate  the  acid  from  the  ter- 
pin hydrate  v/as  to  dilute  the  mixture  with  60  grams  of  ice.  If 
larger  amounts  are  run  better  results  might  be  obtained  by  the 
addition  of  larger  quantities  of  ice.  After  this  mixture  has 
stood  for  two  hours  it  becomes  a solid  mass  of  terpin  hydrate. 

The  transformation  of  the  mixture  into  terpin  hydrate  can  be 
observed  during  the  early  stages  of  the  dilution.  It  is  a ques- 
tion as  to  just  what  this  red  colored  substance  is.  There  is 
no  way  of  separating  the  acid  from  this  oil  without  first  dilut- 
ing the  substance  and  when  it  is  diluted  it  transforms  into  ter- 
pin hydrate..  IN  the  experiment  where  50  grams  of  sulphuric  are 
used,  the  resulting  mixture  is  white.  There  is  a concentration 
between  the  50  percent  and  the  60  percent  sulphuric  where  the 
mixture  changes  from  a white  color  to  a dark  red.  It  might  be 
that  this  red  color  is  caused  by  terpin  being  formed.  After  this 
mixture  has  stood  for  two  hours  and  the  terpin  hydrate  becomes 
becomes  a solid  mass,  it  should  be  allowed  to  drain  for  48  hours. 
During  this  time  some  of  the  sulphuric  acid  will  drain  off.  If 
the  sulphuric  becomes  too  concentrated  in  the  bottom  of  the 
receptacle,  it  will  decompose  some  of  the  terpin  hydrate.  It  is 
for  this  reason  that  the  mixture  is  allowed  to  drain.  It  is 


Page  20. 


allowed  to  drain  48  hours  so  as  to  convert  as  inuch  of  the  re- 
maining unconverted  turpentine  into  terpin  hydrate  as  possible. 
This  conversion  will  take  plac e, because  tne  oil  is  held  in  con- 
tact with  the  acid,.  Also  the  yield  is  increased  15  to  20  per-  • 
cent  when  the  mixture  is  allowed  to  drain.  Probably  one  reason 
why  all  tne  turpentine  is  not  converted  into  terpin  hydrate 
is  that  the  terpin  forms  a globule  around  the  turpentine  and 
prevents  the  turpentine  from  coning  into  contact  with  the  acid, 
the  best  way  to  remedy  this  trouble  is  to  increase  the  speed  of 
the  stirrer  during  the  last  two  hours  of  the  run.  Another  ex- 
planation for  the  incomplete  conversion  is  that  one  of  the  oils 
of  which  turpentine  is  composed  does  not  react  with  the  sulphuric 
acid,  After  the  mixture  has  drained  it  should  be  sucked  dry 
and  washed  several  times  with  cold  water  and  sodium  carbonate 
solution  until  the  washings  are  neutral.  The  terpin  hydrate 
still  has  some  turpentine  in  it  and  this  can  be  removed  by  steam 
distillation.  The  next  step  in  tne  process  is  to  convert  the 
flaky  terpin  hydrate  into  crystals. 


.. 

I 


• * 


. 


Page  21. 


(D)  The  only  process  found  in  the  literature  for  the 
recrystallization  of  terpin  hydrate  was  the  one  given  hy  Vanino 
in  which  he  uses  S6  percent  alcohol  as  a solvent.  It  was  found 
that  ten  grains  of  terpin  hydrate  dissolved  in  30  grames  of  06  per- 
cent alcohol  at  a boiling  temperature  yielded  upon  cooling 
only  five  grams  of  recrystallized  terpin  hydrate.  The  other  5 gra 
ms  of  terpin  hydrate  remained  in  .solution  with  the  alcohol. 
Probably  the  reason  why  all  the  terpin  hydrate  did  not  recrys- 
tallize is  because  the  terpin  hydrate  loses  a molecule  of  water 
and  changes  to  terpin.  The  tendency  for  the  alcohol  to  hold 
the  water  is  probably  greater  than  the  tendency  for  the  terpin 
to  go  back  to  terpin  hydrate.  When  10  grams  of  terpin  hydrate 
are  dissolved  in  30  grams  of  boiling  water  about  25  percent  of 
the  terpin  hydrate  will  go  into  solution,.  This  will  quickly 
recrystallize  when  the  solution  is  allowed  to, cool..  The  follow- 
ing data  is  on  the  recrystallization  of  terpin  hydrate  in  alcohol 
of  different  concentrations. 


Terpin  Hydrate 

Alcohol 

W a tier 

Yield. 

25  grams 

7b  gr.. 

0 gr. 

12  i 

it 

65 

10 

15 

tl 

60 

20 

16 

55 

30 

18 

it 

50 

45 

19 

1*1 

45 

55 

21 

it 

40 

65 

23 

tii 

39. .2 

7 5 

24 

lii 

38 

78 

-- 

It. 

35 

80 

' 


. 


* 


. 


■ 


Page  22, 

It  was  found  easier  to  recrystallize  the  by  first  dissolv- 
ing it  in  35  percent  alcohol*, f il ter  and  dilute  the  mixture;  than 
to  first  dilute  the  alcohol  and  then  filter..  The  reason  for  this 
is  that  the  terpin  hydrate  has  a strong  tendency  to  recrystallize 
in  the  dilute  solution  and  will  usually  stop  up  the  funnel  when 
being  filtered..  Large  crystals  of  terpin  hydrate  are  obtained, 
if  the  mixture  is  diluted  with  hot  water  instead  of  cold  water.. 
The  cold  mixture  should  be  allowed  to  stand  several  minutes  to 
insure  complete  recrystallization..  Care  should  be  taken  that 
the  mixture  and  the  funnel  are  before  filtering.  After  terpin 
hydrate  has  been  filtered  off,  the  solution  should  be  fraction- 
ated and  the  remaining  terpin . hydrate  will  crystallize  out. 

The  yield  is  96  percent. 


« 

4 


. 


Page  23.. 


(E)  The  best  process  for  the  conversion  of  terpin  hydrate 
into  terpineol  is  the  one  worked  out  by  Professor  Roger  Adams.. 

A mixture  of  50  grams  of  terpin  hydrate,  75  grams  of  water  and 
0.89  grams  of  hydrochloric  acid  ( sp.gr.,  1..19  ),  are  refluxed 
for  three  hours.  The  yield,  for  this  process  is  90  percent,.  It 
was  found  that  sulphuric  acid  gave  the  same  results  as  hydro- 
chloric. If  more  than  1.  5 grams  of  acid  are  used,  the  resulting- 
mixture  will  he  composed  of  oils  of  lower  boiling  points  than 
that  of  terpineol..  If  less  than  0.  5 grams  of  acid  are  used,  there 
is  no  reaction,,  unless  the  mixture  is  refluxed  for  six  hours.. 

Ill  Dr.  Adams  process  the  same  results  are  obtained,  if  the  .ix- 
ture  is  refluxed  two  hours  insttead  of  three  hours.  The  temper- 
ature of  the  mixture  should  be  kept  at  100  to  150  degrees  dur- 
ing the  refluxing;  period..  The  terpineol  which  separates  from 
the  mixture  should  be  washed  with  water  until  there  is  no  trace 
of  acid.  Then  the  neutralized  oil  is  distilled  under  diminish- 
ed pressure. 


Page  24. 

VII..  CONCLUSION.. 

^C/0  !(,  s V (O  M * *.  Y -J'n  ,0-ir  "CA>iu 

The  results  of  the  experiments  performed  indicate  that  the 

maximum  yield  for  the  conversion  of  turpentine  into  terpineol  is 
73  percent, The  first  step  in  this  process  is  to  convert  turpen- 
tine into  terpin  hydr<  te.  T t 4,3!  by  weight  of  turpen- 
tine (sp.gr.)  in  a uechanical  st  1:..  c 

with  a cold  nixture  of  three  parts  by  weight  of  sulphuric  acid 
(sp.gr.  1.84),  and  2 parts  by  weight  of  water.  Care  should  be 
taken  that  the  sulphuric  acid  solution  is  added  slow  enough  to  the 
turpentine  so  as  not  to  raise  the  temperature'  of  the  mixture 
more  than  three  degrees.  This  mixture  is  stirred  at  zero  degrees 
for  eight  hours.  3y  the  end  of  this  time  the  mixture  is  convert- 
ed into  a red  colored,  >genous  substance.  This  is  poured  into 
a receptacle  and  two  parts  by  weight  of  ice  are  added.  The  mixture 
is  stirred  for  several  minutes  and  allowed  to  stand  two  hours. 

Then  let  the  mixture  drain  for  48  hours,  suck  dry  and  wash  first 
with  water  and  then  with  sodium  carbonate  solution  until  the 
washings  are  neutral  and  wash  out  the  sodium  carbonate  with  water.. 
Any  coloring  matter  in  the  terpin  hydrate  may  be  washed  out  with 
dilute  alcohol.  The  next  step  is  to  separate  the  unconverted 
turpentine  from  the  terpin  hydrate  by  steam  distillation.  Recrys- 
tallize the  terpin  hydrate  by  dissolving  one  part  by  weight  into 
1. 57  parts  of  95  percent  alcohol  cl  boiling  temperature.  Filter 
this  solution  through  a hot  suction  funnel  and  dilute  the  alcohol- 
ic mixture  with  three  parts  of  water.  The  terpin  hydrate  is  sep- 
arated by  filtering. 


Terpineol  is  made  from  terpin  hydrate  by  refluxing  at 


' 


■ 


' 


' 

. ..  . 

' |S  $ 

. 

■ 

* 

. 

* 

♦ 

• 

. 

, f 

. ' ) 

.. 

• 

. 

• 

. 

• 

'•  ; ' , .. 

i 


p 


125  degrees  for  two  hours  a mixture  of  one  part  by  weight  of 
terpin  hydrate  with  one  and  a half  parts  of  water  containing 
0.  009  parts  by  weight  of  sulphuric  acid  (sp.gr.  1.84),.  The  ter- 
pineol  is  separated  and  washed  with  water  until  the  washings  are 
neutral.  The  oil  is  then  distilled  under  diminished  pressure. 

The  ^ield  is  90  percent. 

The  by-products  from  this  process  will  be  turpentine, 
sulphuric  acid,  alcohol  and  resinous  material.  The  first  three 
by-products  cah  be  reclaimed  and  used  over.  If  terpineol  cost 
eight  times  more  than  turpentine  , then  the  profits  of  the 
process  are  about  S00  percent. 

Terpineol  has  a composition  very  similar  to  that  of 
linalool,  geraniol,  citronellol,  citronel  and  citral.  The  larket 
price  for  these  oils  is  much  higher  than  it  is  for  Lneol.. 

Probably  if  the  proper  acid  is  used  along  with  the  exact  temper- 
ature and  acid  concentration,  turpentine  can  be  converted  into 
any  one  of  these  oils.  The  process  given  in  PRIED., ' 1894-1897 ) , 
converts  linalool,  geraniol  and  citronel  into  terpineol.  In  the 
process  given  in  the  J,.Chem.  Soc.  (1899),  linalool  is  converted 
into  terpineol.  In  the  J.Chem.  Soc.  (1895),  aprocess  is  given  for 
the  decomposition  of  terpin  hydrate  into  acetic  acid  and  oxalic 
acid..  Since  this  reaction  will  take  place,  terpin  hydrate  ought 
to  be  made  on  a commercial  scale  by  the  synthesis  of  acetic  and 
oxalic  acid.  In  the  process  in  the  J.  CJhem.  Soc.  (1893 ) , terpineol 
is  decomposed  into  cynene.  Since  this  reaction  takes  place,  cynene 
might  be  converted  into  terpineol. .Also  cymene  is  made  by  heating 
oinene  dibromide  at  a moderately  high  t emper&ture&nd  dipentene 
can  be  made  by  heating  isoprene  to  260  degrees.. 


Page  26. 


VIII.  BIBLIOGRAPHY. 

Terpin eol. 

Journal  of  the  Chemical  Society  (1917)  l-p513. 

Journal  of  the  Chemical  Society  (1907)  l-ol059. 

" " " " " " 1-P228. 

a ii  ii  it  M ii  1-64 

Annalen  der  Chemie  (230,  p225.  ). 

" " " (230,  p253.  ). 

U. S. Patents.  Volumn  9b,  pl594. 

Friedlaender  (1894-1897)  pl306. 

Journal  of  the  Chemical  Society  (1899)  p63. 

J.  pr.  Chera,  (1898)  (ii)  58,  pl09. 

Comptes  rendu s (1901)  132,  p637. 

Annalen  der  Chemie  (350,  pl55.  ). 

Comptes  rendus  (1907)  (i)  ol62. 

Hagers  Handbuch  der  Pharmazeut ischen  Praxis,  Vol.  II. 

Terpin  Hydrate. 

U.  S.  Patents,  Volume  126.  p642. 

Friedlaender  (1907-1910)  oil 62. 

Journal  of  tne  Chemical  Society  (1395)  p548. 

Cnemisches  Zentralblatt  II,  p419. (1897). 

" " " p420  ” 

Ph.  Ch.  (27  ) pb43. 

Berichte  (35)  p<155. 

Chemisches  Zentralblatt  II,  p417. (1897). 

Terpene 

Berichte  (27)  pi 651. 

" (29)  pi 3. 

" (32)  p57. 

Cornptes  rendus  (1901)  I olOOo. 

" " M fl  p784. 

" " (1902)  « pi 059. 

J.  pr.  (ii)  (66),  p49. 

Comptes  rendes  134,  p360. 


- 


/ 


